Editor’s note: This is an occasional series on ways drivers can make the streets of Manteca safer.Manteca Police Chief Nick Obligacion clearly remembers the day that he let a motorist that he saw drive around downed railroad crossing arms on Center Street go without a ticket.It wasn’t because Obligacion — a gung-ho rookie officer at the time — was being nice.His focus changed after he missed being killed by a few feet doing the same exact thing the motorist did — going around the downed crossing arms.“I was so taken aback by almost being killed by the train that I forgot about the driver,” Obligacion said.Emergency vehicles, with red lights and sirens, are allowed to go around downed crossing arms.It’s something, though, that Obligacion won’t do if he can see a train approaching.“I looked both ways and I saw the train approaching the Yosemite crossing heading for Center,” the chief recalled. “I thought I had plenty of time.”What Obligacion learned that day was that even those who go through extensive training to judge speed such as law enforcement officers, can easily misjudge how fast a train is closing in on them.Having seen more than his share of train-vehicle collisions in Manteca over the years, Obligacion noted trains have a tremendous amount of energy barreling down the tracks at 65 mph. “An average freight train takes a mile or so to come to a stop,” he said.He recalled a collision on Walnut Avenue in Manteca where the driver in a big SUV had gone around the arms and was clipped in the rear bumper by an oncoming locomotive.